According to two properties of the life cycle and to fluctuation with parities, four mathemati- cal models, the Poisson cycle model, the cubic polyno- mial model, the modified quadratic polynomial model- I artd the mo...According to two properties of the life cycle and to fluctuation with parities, four mathemati- cal models, the Poisson cycle model, the cubic polyno- mial model, the modified quadratic polynomial model- I artd the modified quadratic polynomial model-H, were used to fit the records of litter size in Jiangquhai sows. From the viewpoint of statistics and biological significance, the modified quadratic polynomial mod- el-I was found to be the optimum model. A single traitanimal model and DFREML procedures were further used to estimate the heritability values of optimum model parameters. The results show that the heritabili- ty values for the coefficients A and B and the herita- bility value for the acme of the model pure quadric curve are larger than the heritability value for the litter size. This suggests that selection for model parameters may be more effective than direct selection for litter size.展开更多
This study was conducted to investigate the effects of catechins on reproductive performance, antioxidative capacity and immune function of gestating sows. A total of 60 cross-bred(Landrace × Large White) multi...This study was conducted to investigate the effects of catechins on reproductive performance, antioxidative capacity and immune function of gestating sows. A total of 60 cross-bred(Landrace × Large White) multiparious sows were blocked by body weight, parity and backfact and randomly allocated to 1 of 5 treatments: 0.100,200,300, or 400 mg/kg catechins. Dietary treatments were imposed from mating to d 40 of gestation of sows. At farrowing, litter total born, born alive, dead, and normal-(healthy piglets,>0.85 kg) and low-birth weight piglets(<0.85 kg) were recorded. Within 3.00 ± 0.50 days after farrowing litter size was standardized to 8,00 ± 1.50 piglets within treatment. The piglets were weighed at birth(d 1) and weaning(d 28). Sows serum samples were obtained from blood samples collected on d 40 of gestation for analyses of glutathione peroxidase(GSH-Px), superoxide dismutase(SOD), catalase(CAT),malondialdehyde(MDA), hydrogen peroxide(H2 O2), nitric oxide synthetase(NOS) and nitrogen monoxide(NO). Our results showed that supplementation of catechins at levels of 200 or 300 mg/kg led to improvements in litter born alive(P < 0.01) and piglet born healthy(P < 0.01) and a decrease in stillborn(P < 0.05) at farrowing when compared with the control. In comparison with the control, catechins at any supplemental levels all enhanced the serum SOD(P < 0.05) and CAT(P < 0.01) activities of sows at farrowing but no obvious differences in the serum GSH-Px and NOS activities were observed in this trial(P > 0.05). Sows received 200 mg catechin per kg diets showed a reduction(P < 0.05) of the serum MDA level at farrowing compared with all other treatments. Sows received all the levels of catechin showed a reduction(P < 0.05) of serum H2 O2 level compared with sows received the control diet on both d 40 of gestation and farrowing. Our results demonstrated that the catechins may be a potential antioxidant to increase the reproductive performance and antioxidative capacity of sows when it was added into diets during the early gestation.展开更多
文摘According to two properties of the life cycle and to fluctuation with parities, four mathemati- cal models, the Poisson cycle model, the cubic polyno- mial model, the modified quadratic polynomial model- I artd the modified quadratic polynomial model-H, were used to fit the records of litter size in Jiangquhai sows. From the viewpoint of statistics and biological significance, the modified quadratic polynomial mod- el-I was found to be the optimum model. A single traitanimal model and DFREML procedures were further used to estimate the heritability values of optimum model parameters. The results show that the heritabili- ty values for the coefficients A and B and the herita- bility value for the acme of the model pure quadric curve are larger than the heritability value for the litter size. This suggests that selection for model parameters may be more effective than direct selection for litter size.
基金jointly supported by grants from the National Key Technology Research and Development Program of the Ministry of Science and Technology of China(2012BAD39B00)State Key Laboratory of Animal Nutrition(2004DA125184F1305)+2 种基金the NSFC(307005793110173031110103909)
文摘This study was conducted to investigate the effects of catechins on reproductive performance, antioxidative capacity and immune function of gestating sows. A total of 60 cross-bred(Landrace × Large White) multiparious sows were blocked by body weight, parity and backfact and randomly allocated to 1 of 5 treatments: 0.100,200,300, or 400 mg/kg catechins. Dietary treatments were imposed from mating to d 40 of gestation of sows. At farrowing, litter total born, born alive, dead, and normal-(healthy piglets,>0.85 kg) and low-birth weight piglets(<0.85 kg) were recorded. Within 3.00 ± 0.50 days after farrowing litter size was standardized to 8,00 ± 1.50 piglets within treatment. The piglets were weighed at birth(d 1) and weaning(d 28). Sows serum samples were obtained from blood samples collected on d 40 of gestation for analyses of glutathione peroxidase(GSH-Px), superoxide dismutase(SOD), catalase(CAT),malondialdehyde(MDA), hydrogen peroxide(H2 O2), nitric oxide synthetase(NOS) and nitrogen monoxide(NO). Our results showed that supplementation of catechins at levels of 200 or 300 mg/kg led to improvements in litter born alive(P < 0.01) and piglet born healthy(P < 0.01) and a decrease in stillborn(P < 0.05) at farrowing when compared with the control. In comparison with the control, catechins at any supplemental levels all enhanced the serum SOD(P < 0.05) and CAT(P < 0.01) activities of sows at farrowing but no obvious differences in the serum GSH-Px and NOS activities were observed in this trial(P > 0.05). Sows received 200 mg catechin per kg diets showed a reduction(P < 0.05) of the serum MDA level at farrowing compared with all other treatments. Sows received all the levels of catechin showed a reduction(P < 0.05) of serum H2 O2 level compared with sows received the control diet on both d 40 of gestation and farrowing. Our results demonstrated that the catechins may be a potential antioxidant to increase the reproductive performance and antioxidative capacity of sows when it was added into diets during the early gestation.